布比卡因和罗哌卡因对犬鞘内注射引起脊髓神经毒性程度的研究

Study on the degree of spinal neurotoxicity caused by bupivacaine and ropivacaine intrathecal injection in dogs

目的观察不同浓度剂量局麻药鞘内注射对犬脊髓、神经根超微结构和脑脊液(CSF)的影响。方法 30只犬分为5组,鞘内分别注入生理盐水、均0.5%和0.75%的布比卡因及罗哌卡因(均2 mL)。测定CSF中氧分压及乳酸值;观察脊髓及神经根超微结构并检测其Ca2+、MDA含量及SOD活力。结果 5组间进行两两比较的单因素方差分析显示,氧分压、乳酸值、Ca2+、MDA含量及SOD活力比较,差异均无统计学意义(P>0.05)。0.5%组,脊髓、神经根超微结构基本正常;0.75%组,脊髓部分神经元胞质内少量线粒体变性,部分有髓神经纤维板层结构疏松。结论 0.5%较0.75%的局麻药鞘内注射对脊髓、神经根超微结构的影响轻微,推荐使用0.5%局麻药。

Objective To investigate the effects of intrathecal anesthesia with different concentration and doses of local anesthetics on spinal cord, nerve roots and cerebrospinal fluid （CSF） in dogs. Methods Thirty dogs were randomly divided into five groups. Normal saline, 0. 5% and 0. 75 % bupivacaine, 0. 5 % and 0. 75 % ropivacaine （2 mL） were in- trathecally injected in each group, respectively. CSF lactic acid and PO2 levels were measured. Spinal cord and nerve roots were removed for Ca2 ~, malonaldehyde （ MDA ） contents and superoxide dismutase （ SOD ） activity determination and electron microscopic examination. Results The datas detected have no significant differences in all groups （P 〉 0.05）. The uhrastructure of spinal cord and nerve roots were basically intact in 0.5% groups, but a small amount of mitochondria vacuolar de- generation were found in partial neuronal cytoplasm of spinal tissues in 0. 75% groups. Conclusion Compared with 0. 75% groups, there were less adverse effects on spinal cord and nerve roots in 0. 5 % groups.